The invention relates to a drum type machine for the treatment of batchwise textile material, especially a washing machine, with at least one driven drum rotatable supported in an approximately horizontal position and having a central opening in one end wall for loading purposes and a central opening in the other end wall for unloading purposes, as well as a conveying paddle in the interior for moving the batch of material in the drum and for the axial transporting of the batch of material through the unloading aperture in the other direction of rotation of the drum.
Drum-type machines have been known wherein the drum is loaded through one end wall and again unloaded through the other end wall. The unloading of the batch of material present in the drum is either controlled chronologically, i.e., the drum rotates for a preset period of time for unloading purposes, or it is controlled in dependence on the direction of rotation, i.e., the unloading is executed by reversing the direction of rotation, essentially during one full revolution of the drum. In the latter method, the batch of material is fed mechanically and forcibly by means of a conveying paddle to the unloading aperture. The adjustment and construction of the drum in the two conventional processes is based on experiential values indicating when normally all pieces of the batch of material have left the drum. However, due to unforeseeable influences, it can happen repeatedly that, after termination of the preprogrammed unloading step, not all pieces have been discharged as yet from the drum, and such pieces are in almost all cases in the zone of the unloading aperture, for example they have become jammed at that point. This not only results in an intermixing of various batches of materials, but also in disturbances during the treatment procedure, especially in case of multiple-drum machines, e.g. washing machines, so that the machine can clog up under certain circumstances, whereupon it can be returned into operation only under considerable expenditures of work and time.
It is an object of this invention to provide a drum-type machine improved in this respect, wherein the conveyance of the batch of material through the drum is effected in a controlled fashion.
This object is attained, in accordance with a preferred embodiment of the invention, by providing a sensor with a feeler oriented into the loading and/or unloading aperture, wherein the feeler is changed by the batch of material moved through the loading and/or unloading opening.
In a further embodiment of the invention, a particularly advantageous construction is obtained by arranging the sensor in the lower zone of the loading and/or unloading aperture with a preferably upwardly directed feeler.
Another feature of the invention is characterized by connecting the sensor with a switching device, especially for the drum drive mechanism.
The advantages attained by this invention reside particularly in that the sensor monitors at the loading and/or unloading aperture of the drum the passage of the batch of material during the conveying phase. Each part of the batch of material remaining in the zone of the aperture produces a signal indicating or directly initiating a correction. By arranging the sensor in the lower zone of the aperture, it is thus also possible to detect individual pieces, particularly those having small dimensions, with certainty. By connecting the sensor with a switching device, the control of the machine can thus be directly affected, for example, the drum drive mechanism can be additionally controlled, in order to eliminate the disturbance. Furthermore, it is possible to produce signals for the operating personnel so that possibly a manual intervention can take place to avoid large-size interruptions or blockages. The provision of the sensor at the loading and/or unloading aperture therefore results in an increased safety during the automatic operation of a drum which can be loaded and unloaded axially, especially in case of multiple-drum machines, namely with respect to the optimum separation of the batches, as well as an increased operating safety.
These and further objects, features and advantages of the present invention will become more obvious from the following description when taken in connection with the accompanying drawings which show, for purposes of illustration only, several embodiments in accordance with the present invention.